Rotor casting machine



Dec. 22, 1936. DOLAN Er AL 2,065,213

ROTOR CASTING MACHINE Filed Jan. 16, 1931 3 Sheets-Sheet 2 l I *74 j; if Z lays: j I: .90 m;

4 7 f 42 2 l 74L 92 7 w! 50 a hi i i 5 11M l 1'" N 1' -i A 5% i gunum 37 I Dec. 22, 1936. E. F. DOLAN ET AL ROTOR CASTING MACHINE Filed Jan 16, 1931 3 Sheets-Sheet 3 Patented Dec. 22,, 193s -U-NlTE-D STATES PATENT, OFFICE 2,065,213 no'ron. cAsrmc mcnma Edward F. llolan, .Los Angeles, and Henry C. Mellon, Pasadena, Calif., assignors to U. S.

Electrical Motors, Inc.

fornia:

, a corporaticn of Cali-' Application January is, 1931, Serial No. 509,072

, 12 Claims. Our invention relates tothe art of casting and relates to a device for casting bus-bars in the rotors of synchronous motors. Although our invention has a wide variety of uses, we are at the present time employing it in the casting of.

rotors for electric motors. These rotors are made with a laminated core of stampedplates with notches in their edges aligned so as to form busbar channels in the periphery of the rotor in which the bus-bars are formed by casting a metal, such as aluminum, therein. At the ends of the rotor and the ends of the bus-bars, busbar connector rings and fan blades are integrally formed with the bus-bars. These fan blades or vanes produce a circulation of air and are in direct contact with the air. In addition to this, the fan blades are integrally formed with the bus-bars and the bus-bar connector rings so that heat generated therein due to a flow of electric energy through the bus-bars and bus-bar connector rings is readily conducted to the fan blades by which it is dissipated into the circulating air. a

It is an object of our invention to provide a casting device which is especially adapted to casting of the electrical elements in motor rotors by introducing melted' aluminum through the base or bottom plate of the mold and raising the aluminum therein so as to completely fill the mold without formation of air spaces therein.

A further object of the invention is to provide a device of .this character which will auto-v matically free the end plates of the mold from the casting and will remove the metal gates formed at the lower end of the casting in the inlet openings of the mold, thereby considerably reducing the labor involved.

It is a further object of the invention to provide a simple form of device for applying the melted metal to the mold under pressure. In the preferred form of this device a cylinder is formed under the mold, and a piston is operable vertically within the cylinder to upwardly displace and force into the mold the greater portion of a quantity of melted metal with which the cylinder has been charged preparatory to a casting operation. It is preferable 1.0 place in the cylinder a quantity of melted metal greater than required in the casting. When the casting operation is completed, therefore, a residue or disc of metal remains in the upper portion of the cylinder and is connected to the casting through the gate portions formed in the gates of the mold. The invention provides means for preventing raising of the residue from a specified position and means for raising the casting with sumcient force-to break'off the gate portions as the final step in the casting operation, making it then possible to easily remove the mold and casting from the casting device.

A further object of the invention is to provide a means for engagement of the residue with the piston in such a manner that the residue cannot be removed from the piston except in a lateral direction. This enables the residue to be held down while the casting is being raised, thereby severing the residue from the casting in the manner above described. A further object of the invention is to provide ta. casting machine having a mold with end pieces, means for holding the parts of the mold tightly together during the introduction of solidifiable material thereinto, and means for moving the end pieces of the mold outwardly so as to free them from the casting.

In the preferred practice of the invention the mold is made with a central part and two end plates. In the operation of the casting device the upper end plate is first lifted so as to be freed from the upper end of the casting, and the central part of the mold is then lifted from the lower end piece so as to free the lower end of the casting from the end piece.

Further objects and advantages of the invention will be made evident throughout the following part of the specification.

Referring to the drawings, which are for illustrative purposes only,

Fig. 1 is a vertical cross section throlmh a casting device embodying the principles of our invention, this view showing the-base and superstructure of the casting device.

Fig. 2 is a partly sectioned view showing the injector piston in partly raised position.

Fig. 3 is a view showing the head in raised position, for the purpose of illustrating the manner in which the device functions to free the end plates and sever the gate portions from the casting.

Fig. 4 is an enlarged cross section on a plane represented by the line 44 of Fig. 1.

Fig. 5 is an enlarged cross section on a plane represented by the line 5-5 of Fig. 1.

Fig. 6 is a fragmentary view showing the injector piston in fully raised position.

Fig. 7 is a plan view corresponding to Fig. 6.

Figs. 8 and 9 are perspective views showing the liner members.

In the preferred embodiment of our invention shown in Fig. l, we provide a base or table structure it supported on legs is, and superstructure it supported on. posts 84. The device employs a movable head 55 including a vertical bar it having a piston ill on its upper end which is received in a cylinder i8 formed in and supported by the superstructure E3. The lower end of the cylinder 58 is closed by a plate 118 having a packing means 29 for preventing leakage around the bar or shaft 16 so as to enclose a pressure chamber 22 adjacent the lower face of the piston thand upper and lower pipes 23 and 24 communicate with the upper pressure chamber 25 and the lower pressure chamber 22 for admitting fluid under pressure to the respective chambers so asto selectively raise and lower the head l5. The table I! is 4 provided with an opening 28 in which a metal reservoircylinder 21 is supported in such position that the upper end of the cylinder 21 is substantially level with the upper face of the table H. In the cylinder 21 is an injector piston 28 which is secured to the upper end of a con-- necting rod 38 which projects through packing means 3| supported in a plate 32 which is secured to the lower end of the cylinder 21 by means such as screws .33. On the lower end of the connecting rod is an actuating piston 34 which is received in an actuating cylinder 35 having upper and lower pipes 36 and 31 communicating with the upper and lower pressure chambers 38 and 38 thereof. Fluid under pressure may be applied through the pipes 36 and 31 to produce upward and downward movement of the piston 34, which movement is transmitted through the connecting rod 38 to the piston 28 of the reservoir cylinder 21. The practice of the invention employs a source of fluid under pressure and valves for controlling this fluid in a manner" to selectively operate the pistons l1 and 34, but in view of the fact that such devices are old and well known, illustration thereof is thought unnecessary.

A-mold 4|, consisting of a central cylindrical part 42 and upper and lower end pieces or plates 43 and 44, is disposed between the reservoir cylinder 21 and the head I5. The central portion of this mold, as shown in Fig. 4, is .formed of cooperating halves 45 and 46 which are hinged together by means of a hinge pin 41 and a clamp 48. The clamp 48 is hinged by means of a pin 58 to a lug 5| projecting from the part 45 and has a clevis portion 52 adapted to swing over a lug 53 projecting from the part 46. When the clamp 48 is swung outwardly, the central part 42 of the mold 4| may be opened by swinging the cooperating halves 45' and 46 outwardly on the hinge pin 41. The interior cylindrical face of the central part 42 is of such diameter that it will closely fit the rotor punchings 54 and has the ends thereof counterbored, as indicated at 55 and 56, to receive the end pieces 43 and 44 which are provided with a suitable cooperative configuration. The upper end plate 43 is secured to the head i5 by means of a flange 51 which is removably secured in place by means of a set screw 58. Downwardly extending from the flange 51 are lifting hooks 68 having inwardly extending portions 6| at their lower ends which project under a radially extending flange 62 or other similar projection on the central part 42 of the mold 4|. The hook members 6|)v are hinged to the flange 51 at 63, and compression springs 64 operate between the upper ends 65 of the hook members 68 and brackets 66 on the flange 51 to resiliently hold the members 6| of the hooks 68 in inward position.

aoeaaic an annular channel or passage E3 on the lower face of the flange 57, this passage it having continuation openings 14 extending upwardly therefrom through the flange 5?.

The lower end piece 44 is preferably provided with an annular shoulder 15 adapted to fit in a counterbore 16 in the upper end of the cylinder 21, and upwardly tapering gates 11 are extended from the lower face of the end piece 44 to the bottom ends of, the recesses 18. A centralizing pin 18 extends upwardly from the lower end piece 44 and serves to axially align the punchings 54. When the mold is closed, as shown in Fig. 1, the upper end of the pin 18 is received in a concentric opening in the lower end of the boss 81 of the upper and piece 43. The upper portion of the injector piston 28 is provided with a dovetail slot 82 the side walls of which diverge from one end to the other so that a body of metal which hardens in the slot can be removed laterally without binding so as to resist removal but cannot be raised from the piston 28.

In the operation of the device the following procedure is followed: A bottom insulator 84 of the shape shown in Fig. 9 is placed in the cylinder 21 on and in engagement with the upper face of the piston 28. This insulator consists of a sheet of asbestos paper having the central portion 85 thereof folded so as to form. a dovetailed tapered groove which will flt into the groove 82 in the upper face of the piston 28. The sides or wings 86 of the insulator 84 are circular segments of such size that the upper face of the piston 28 is substantially covered. A wall insulator 81, consisting of a rectangular sheet of asbestos paper rolled to cylindrical form as shown in Fig. 8, is then placed in the cylinder above the bottom insulator 84 in the manner shown,

1 thereby insulating the metal walls of the reservoir Then, by introduction of fluid into the upper pressure chamber 25 of the cylinder Hi, the head is forced downwardly and presses the upper end piece 43 into the center part 42 of the mold 4| tightly together. The assembly of punchings 54 is compressed between the bosses 61 of the upper and lower end pieces 43 and 44. At this time air or other fluid under pressure is introduced through the pipe 31 into the lower pressure chamber 38'of the actuating cylinder 35, causing the piston 34 to impel the piston 28 upwardly so as to upwardly displace the body of melted aluminum through the gates 11 into the interior of the mold 4|. As shown in Fig. 2, this body of melted aluminum is displaced upwardly within the mold as indicated at 90 so as to displace all of the air in the spaces of the mold and to completely fill the mold.

It is a feature of the invention to provide a number of narrow recesses 92 in the side walls of the center part 42 of the mold into which a portion of the melted aluminum will enter as shown and will therein solidify so as to form means for engagement between the casting and the center part of the mold for preventing axial movement of the casting in the center part of the mold during the freeing of the end pieces 43 and 44 from the casting and the breaking of the gate portions 93 consisting of metal solidified in the gates 11. If desired, a pair of hold-down brackets 94 may be employed to hold the lower end piece 44 down during theraising of the head, but in the general use of the invention these hold-down brackets are not necessary for the reason that the gate portions 93 are sufdciently strong to hold the lower end piece 44 down during the initial raising of the head to free the upper end piece 43 from the upper portion of the casting formed therein. These brackets are slotted as indicated at 89 in Fig. 5 so that they may be moved inwardly and outwardly.

In Fig. 3 the head I5 is shown in raised position, and in this view the operation of the mechanism in freeing the'end pieces from the casting and severing the gate portions 93 is represented. This final operation is accomplished in the following steps: After the melted metal has solidi- .fied in the mold under pressure, fluid is delivered through the pipe 24 into the lower chamber 22 of the cylinder l8 to move the head l5 upwardly. As indicated by dotted lines 95' in Fig. 3, a body 95 of solidified metal or residue is formed between the upper face of the piston 28 and the lower face of the lower end piece 44, and this residue is locked to the piston 28 by a dovetail rib 96 cast in the dovetail groove 82 of the piston. The residue 95 cannot therefore be raised from the piston, and the rotor casting cannot be raised without breaking the gate portions 93; therefore, the first upward movement of the head I 5 results in freeing the upper end plate 43 from the upper end of the casting and lifting the upper end piece into a position above the upper vanes 91 of the rotor casting, as shown in Fig. 3. At this time the hook members 60 engage the flange 62 so that the continued upward movement of the head l5 results in pulling the lower portion of the casting upwardly relative to the lower end piece 44 and further results in severing the gate portions 93 on the plane where these gate portions join the lower ends of the lower vanes 98 of the rotor casting.

By introduction of fluid through the pipe 36 into the upper chamber 38 of the cylinder 35, the piston 34 is caused to move the piston 28 downwardly so as to carry the residue 95 downwardly therewith as indicated in full lines, this downward movement of the residue 95 resulting in removal of the gate portions 93 from the gates 11, whereupon the center part 42 and the lower end piece 44 may be removed laterally from position under the head IS. The piston 28 is then raised into an upwardly projecting position, as indicated in Fig. 6, so that the residue 95 is supported in position above the top of the table II, whereupon force exerted against the residue in the direction indicated by an arrow I89 in Fig. '7 will result in the tongue or rib 96 sliding rearwardly in the groove 82 and the residue 95 moving in a lateral and rearward direction from engagement with the piston 28. The piston 28 is then lowered to fully retracted position, as shown in Fig. 1, ready for a consecutive casting operation. The gates 11 and the gate portions 93 converge upwardly, thus making the smallest diameter of the gate portions 93 adjacent the points at which they meet the lower ends of the vanes 98. As a result of this upward convergence, the gate portions 93 cannot be pulled through the gates I1, and therefore breakage occurs at the upper ends of the gate portions .93 when the casting is moved upwardly with the center part 42. The bodies of metal extending-into the recesses or grooves 92 in the center part 42 of the mold positively move the casting upwardly with the center part 42 when the center part 42 is raised by the hook members 60. Upon removal from position under the upper end piece 43, the center part of the mold may be opened and removed from the casting and then closed and replaced on the lower end piece 44 ready for a consecutive casting operation.

Although we have herein shown and described our invention in simple and practical form, it is recognized that certain parts or elements thereof are representative of other parts or elements which may be used in substantially the same manner to accomplish substantially the same results; therefore, it is to be understood that the invention is not to be limited to the details disclosed herein but is to be accorded the full scope of the following claims.

We claim as our invention:

1. A casting device of the character described, including: a table member having an opening; a reservoir communicating with said opening; a mold adapted to be placed over said opening, said mold having an upper end piece, a central part, and a lower end piece, said lower end piece having a gate opening therethrough communicating with said reservoir in said table member; means for forcing metal from said reservoir through said gate opening into the interior of said mold; an upwardly movable member adapted to hold the parts of said mold together, said upwardly movable member being secured to said upper end piece so as to raise said upper end piece therewith; means carried by said upwardly movable member for engaging and lifting said central part after said upper end piece has been moved a predetermined distance; and means for moving said upwardly movable member.

2. A casting device of the character described,

including: a table member having an opening; a reservoir communicating with said opening; a mold adapted to be placed over said opening, said mold having an upper end piece, a central part, and a lower end piece, said lower end piece having a gate opening therethrough communicating with said reservoir in said table member; means for forcing metal from said reservoir through said gate opening into the interior of said mold; an upwardly movable member adapted to hold the l parts of said mold together, said upwardly movable member being secured to said upper end piece so as to raise said upper end piece therewith; hook members for lifting said central part after said upper end piece has been moved a predetermineddistance; and means for moving said upwardly movable member.

3. A casting device of the character described, including: a table member having an opening; a reservoir communicating with said opening; a mold adapted to be placed over said opening, said mold having an upper end piece, a central part, and a lower end piece, said lower end piece having a gate opening therethrough communicating with said reservoir in said table member;. means for forcing metal from said reservoir through said gate opening into the interior of said mold; an upwardly movable member adapted to hold the parts of said mold together, said upwardly movable member being secured to said upper end piece so as to raise said upper end piece therewith; hook members for lifting said central part after said upper end piece has been moved a predetermined distance; means for moving said upwardly movable member; and means for holding said lower and piece substantially immovable during the raising of said central part of said mold.

4. A casting device of the character described, including: a table member having an opening; a reservoir communicating with said opening; a mold adapted to be placed over said opening, said mold having an upper end piece, a central part, and a lower end piece, said lower endvpiece having a gate opening therethrough communicating with said reservoir in said table member; a piston vertically movable in said reservoir for forcing melted metal through said gate opening into the interior of said mold, there being a dovetail slot in the upper face of said piston; and means for upwardly moving in consecutive order said upper end piece and said central part.

5. A casting device of thecharacter described, including: a table member having an opening; a reservoir communicating with said opening; a mold adapted to be placed over said opening, said mold having an upper end piece, a central part, and a lower end piece, said lower end piece having a gate opening therethrough communicating with said reservoir in said table member; a piston vertically movable in said reservoir for forcing melted metal through said gate opening into the interior of said mold, there being a dovetail slot in the upper face of said piston; means for upwardly moving in consecutive order said upper end piece and said central part; and insulating means for insulating the upper face'of said piston from the melted metal placed in said reservoir, said insulating means having a wall portion bent so as to rest against the walls of said dovetall slot in the upper end of said piston.

6. A casting device of the character described, including; a table member having an opening; a reservoir communicating with said opening; a mold having an upper end piece, a central part, and a lower end piece, said lower end piece forming a removable closure for said opening and having a gate opening formed therethrough for pro-- viding a passage from said opening to the interior of said mold; means for holding said mold parts in casting position during a casting operation; means for forcing melted metal from said reservoir through said gate opening into the interior of said mold so as to form a casting therein; and means for separating said casting from said upper and lower end pieces and from the solidified portion of said metal remaining in said reservoir; said separating means including, means for holding said casting within said central part of said mold, means for releasably locking said lower end piece to said table member, a member movably supported with respect to said table member, means responsive to a movement of said movably supported member for consecutively separating said central part and the casting retained therein from said upper end piece and from said lower end piece and the solidified metal retained thereby within said reservoir, and means for moving said movably supported member.

7. A casting device of the character described,

,for said opening,

including; atable member having an opening; a reservoir communicating with said opening; a mold having a main body and a lower end piece; said lower end piece forming a removable closure and having a gate opening therethrough for providing a passage from said opening to the interior of said mold; means for holding said mold parts in casting position during a casting operation; means for forcing melted metal from said reservoir through said gate opening into the interior of said mold so as to form a casting therein; and means for separating said casting from said lower end piece and from the solidified portion of said metal remaining in said reservoir; said separating means including, means for holding said casting within the main body of said mold, means for releasably locking said lower end piece to said table member, a member movably supported with respect to said table member, means for locking said main body of said mold to said movably supported member so as to move therewith, and means for moving said movably supported member so as to separate said main body of said mold and the casting retained therein from said lower end piece and the solidified metal retained thereby within said reservoir.

8. A casting device of the character described, including; a mold having a pair of end pieces and a central part; means secured to one of said end pieces for supporting a core member within said mold; supporting means having a pair of relatively movable members for holding the parts of said mold in casting position during a casting operation; and means for separating said end pieces and said core supporting means from the core and the casting formed thereon, said separating means including means for locking said casting to said central part, one of said end pieces being secured to one of said relatively movable members, the other of said end pieces being secured to the other of said relatively movable members, and means for producing a separating movement of said relatively movable members with respect to each other and with respect to said central part so as to free said end pieces from said casting and core member retained within said central part,

9. In a machine for casting conducting metal into cooperative relation with respect to a stack of laminations, a mold body adapted to enclose a stack of laminations, a common movable means for closing one end of the body and for compressing said stack, means for passing molten metal into the mold body, and means whereby movement of said common means in mold opening direction permits only a limited motion between said common means and the mold body, after which the common means lifts the mold body.

10. In a machine for casting conducting metal into cooperative relation with respect to a stack of laminations, a mold body adapted to enclose a stack of laminations, a common movable, means for closing one end of the body and for compressing said stack, means for passing molten metal into the mold body, and means whereby movement of said common means in mold opening direction permits only a limited motion be tween said common means and the mold body, after which the common means lifts the mold body, said means being disengageable at will from the mold body to permit further motion between said common means and the mold body.

11. In a machine for casting moltenmetal, a mold body, movable means for closing one end of the body, means for passing molten metal into the mold body, and means whereby movement of said movable means in mold opening direction serves, at the beginning of the movement, to separate said movable means and said body, and means for limiting the extent of separation between said movable means and said body whereby the movable means lifts the body upon continued movement of said movable means.

12. In a machine for casting conducting metal into cooperative relation with respect to a stack of laminations, a mold body adapted to enclose a stack of laminations, a common movable means for closing one end 'of the body and for compressing s-aid stack, a support for the body, means for passing molten metal into the body, said body having one or more recesses whereby it is temporarily keyed by the metal to the casting, and means whereby movement of said common means in mold opening direction permits a limited relative motion between said common means and said body, further movement of said common means lifting said body together with its keyed 1o casting off the support.

EDWARD F. DOLAN. HENRY C. MELLON. 

